Steam-boiler



A. M. OOYLE.

STEAM BOILBR.

(No Model.)

NO. 365,971. Patent'ed July 5, 1887.

wu W W hm mow] ma., w w /W w Wiimoo v I I *UNITED TATES PATENT imion.

ANDREV M-. COYLE, OF VASHINGTON, DISTRICT OF COLUMBA, ASSIGNOR TO W. B.DUNNING, OF GENEVA, NEVV YORK.

STEAM-BO'ILER.

SPECIFICATION forming part of Letters Patent No. 365,971, clatel July 5,1887.

Application] filed May 25, 1887. Serial No. 239,319. (No model.)

To aZZ wii/0171, it may concern:

Be it known that I, ANDRW M; CoYLE, of Vashington, in the DistrictofColumbia, have invented certain newl and useful Improvements inStcanrloilers, of which the following is a specification.

This invention relates to steam boilers of that class in which theproducts of combustion .are eompelled to pass downward in their transitfrom the fire-box to the' smoke-fine; and the invention consists inproviding means fora direct draft, as hereinafter described.

Fignre 1 is a ,Vertical central section of a boiler and its setting withmy improvement, applied thereto. Fig. 2 is a perspect-ive view of thefire-door case, shown detached, with my improvement applied thereto.

My improvement is designed to be applied more especially to what isknown as the Dunning boiler, which is extensively used for heatingbuildings, and the construction of which is so well known that adetaileddescrip' lion is deenied unnecessary. There are, however, other boilersof a similar Character to which my invention may be appliedlwith equalfacility and advantage.

As is well known, and as shown in Fig. 1, the Dunning boiler is made inan upright form, with the fire-box located centrally within the body ofthe boiler at its lower portion, and with a fuel reservoir or magazine,M, located centrall y within the upper part of the firebox.

In the drawings, Fig. l, B indicates the boiler, O the grate, M themagazine, and A the brick-work within which the boiler is set.

H indicates a rectangular casing set in the brick-work at thefrontandproj ect-ing through the side of the boiler to the fire-box,this casing heretofore having been made with tight walls or sidcs andWith a fire-door, F, hinged at its enter end, so it can be opened to getat the fire within the boiler whenever necessary, and which is alsoprovided with a valve, e, for the admission of air to mingle with thegases arising from the burning coal, in order to secure a more perfectcombustion of the gases. As Originally constructed the products ofcoinbustion first passed upward within the fire-box, then down through aseries of Vertical tubes, n, and thence up through the space between theoutside of the boiler and the surrounding brick-Work, as indicated byarrows on the right-hand side of Fig. 1, until intercepted by thehorizontal wall or diaphragm b, which deflects them and causes them topass around the sides ot' the boiler to the front, where an opening isleft in the diaphragm b, through which they pass, then divide and passback around opposite sidcs of the boiler to the outlet or smoke fiue T,which is connected with the ehimney in any 'convenient manuer.Experience has shown that while there is no difficulty'in inducing thesmoke, dnc., to 'follow this circuitous route after the fire is wellunder way and the chimney and all the parts have become heated, so as tocreate a good draft, still there is difficulty when the tire is firststarted, and when of course the boiler and all the fiues are cold.Various plaus have been devised to obviate this difliculty,'such asextending/a smoke flue from the fire-box up through the top of theboiler, and also in making an opening through the side of the boiler atthe upper edge of the fire-box, as shown in the Patent to NV. B.Dunning, September 28, 1886, No. 349,699; but these plans require achange in the construction of the boiler itself, and as these parts mustbe made steam-tight they add more or less to the cost of the boiler. Toebviatethese objections, and at the same time provide a direct draftthat will accomplish the desircd result and at less cost, Isimply makean opening, I, in one of the walls of the cast-iron case or box, H, at S5 a point coincident with the space between the boiler and thebrick-work, as shown in Fig. '1, and provide a sliding plate or daniper,J, by which said opening can be closed or opened at will. In Fig. 1 Ihave shown the slide J go `arranged on the inside of the box or case H,f and it may be provided with asmall rod or handle, a, projecting outthrough the flange at the front or outer end of the case H, as shown inFig.l 2. As, however, the case H is provided with a door, F, at itsfront that can be opened, it isiobvious that the rod a maybe dispensedwith and the slide be moved by the hand or by a poker. In Fig.2 I haveshown the slide J arranged on the outside 1:00 of the case H, in whichcase the haudle a will be necessary, although, if preferred, the

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slide J may be provided with a lug or projection on its under` side andmade to project down through a slot made in the upper wall of the case,so that it can be moved from the inside of the case the same, as whenarranged as in Fig. 1, these being mere matters of detail for the choiceof the constructor, it only being necessary' that it be provided withmeans for moving the slide J forward or 'back at will. It will beobvious that theopening I may be made in the side walls of the case H,either in one or both, and operatejust the same; but I prefer to make itin the top wall, as it is a little more in the direct line of t-hedraft.

This improvement is equally applicable to the surface--burning Dunningboiler, which is the same in construction, exeept that it has nomagazine, but has the Vertical tubes and smoke-passages the same, and'has the front fire-door and case the same. So, too, it is applicable toany style of Vertical boiler which has a reverse draft and a frontfire-door-and case, and which are common in various boilers of thisgeneral Character, of which several styles are now made. It will at oncebe seen that. this improvement requires no change whatever in the'boileritself, and that the additional cost is a mere trifie, it only beingnecparts, including the brick-work, remaining precisely as they werebefore' It is common with the smaller sizes of these boilers tosubstitute a Sheet-metal casing for the brick setting, but that ofcourse will make no difference With this improvement, it being appliedto them in the same inanner pr'ecisely.

Having deseribed myi nvention, what I clairn 15-- 1. In combination witha steam-boiler, substantially such as described, the` case H, providedwith the opening I, and a slide or damper, J, for closing the same,substantially as and Vfor the purpose set forth.

2. The combination, with a Vertical boiler having a fire-box Within itand tubes or passages through which the products of combustion normallypass downward before they reach the exit or smoke-fiue, of the case H,extending through the side of the boiler to the fire-box within, saidcase being provided with a direct-draft opening arranged to eoincidewith the outer smoke-passage, and a damper for closing the same,substantiallf,7 as shown and described.

In witness whereof I hereunto set my hand in the prcsence of twowitnesses.

I ANDREW M. COYLE.

Vitnesses:

W. C. DODGE, ARTHUR AsHLEY.

